Co-Catalyzed Reductive Cyclization of Acrylate-Containing 1,6-Enynes.

A Co-catalyzed reductive cyclization of acrylate-containing 1,6-enynes is reported, providing an approach to construct five-membered carbocyclic and heterocyclic scaffolds containing enol ethers and all-carbon quaternary carbons. This novel process enables an E / Z mixture of 1,6-enynes to react with good functional group tolerance and good isolated yields, in an operationally simple manner.